报告题目:From Li-ion Technology to Post-LithiumSystems
报 告 人:Prof. Helmut Ehrenberg
Institute for Applied Materials (IAM), Karlsruhe Institute of
Technology(KIT), Germany
报告时间:2018年11月1日(星期四)下午14:00-15:30
报告地点:尊龙凯时中心校区唐敖庆楼9楼会议室
报告简介:
Li-ion batteries are at present the best choice ofmobile energy sources with respect to high energy and power densities,lifetime, safety and costs simultaneously. Diffraction methods usingsynchrotron and neutron radiation are extremely powerful methods to revealstructural changes in the underlying electrode materials during cycling undermost realistic operation conditions. Neutrons are essential to localize Li-ionsreliably and to penetrate cell housing in large commercial cells. Selectedexamples are shown for oxides, phosphates and thiophosphates as solidelectrolytes in Li-ion batteries, where the Li-ion diffusion pathways can berevealed from high-quality neutron diffraction data by Rietveld refinements andMaximum-Entropy Methods. Spatially resolved neutron diffraction can revealinhomogeneity of the Li-distribution in large cylindrical 18650-type cells.Furthermore, phase formation beyond equilibrium is observed over a broad rangeof temperatures for the lithiation of graphite .
Costs, availability and sustainability reasons triggerthe development of electrochemical energy storage devices beyond lithium. Themain driving forces are presented and discussed. Selected examples are shownfor Na- and Mg-ion batteries and hybrid batteries with more than one mobile ion inthe electrolyte. In such hybrid concepts for example Mg can be plated at thenegative electrode, while Li- or Na-ions can be intercalated into positiveelectrode materials, where Mg-insertion is hindered.
This work contributes to the research performed atCELEST (Center for Electrochemical Energy Storage Ulm-Karlsruhe).